Abstract: In this study, PVDF-HFP-based porous polymer electrolyte membranes for lithium-ion battery have been prepared by non-solvent evaporate method, and the effects of different volatility temperature ethylene glycol on the structure and properties of porous polymer electrolyte membranes were examined. The membranes were characterized by scanning electron microscopy (SEM), different scanning calorimetry (DSC), mechanical strength test, electrochemical impedance spectroscopy (EIS). The results show that volatility temperature ethylene glycol has significant influences on the physical and electrochemical properties of porous polymer electrolyte membranes. It is found that the membrane with good appearance cannot be obtained at lower temperature. The membranes showed honeycomb-like macroporous morphology on the cross-section. When temperature increased from 60 to 100 ℃, the tensile strength increased from 6.49 to 21.39 MPa, and the ionic conductivity at room temperature decreased from 1.07 to 0.14 mS·cm-1. So with volatility temperature ethylene glycol of 70～90 ℃, it is more suitable for preparing PVDF-HFP porous electrolyte membranes via non-solvent evaporate method.

Key words: lithium-ion battery, polymer electrolyte, non-solvent evaporate method, PVDF-HFP, drying temperature